Non-steroidal anti-inflammatory analgesics such as ketoprofen have excellent anti-inflammatory and analgesic effects and are therefore included as drug components in various forms of transdermal preparations including patches such as gel patches and plasters, as well as gels, creams, ointments, liniments and the like. However, when a transdermal preparation is used that contains, as an active ingredient, a non-steroidal anti-inflammatory analgesic which is a photosensitive compound, photodermatosis is developed as a side-effect, in some rare cases.
Skin irritation such as photodermatosis is a sensitive dermatitis symptom, including erythema with itching or eruption, due to exposure of a photosensitive compound such as ketoprofen to ultraviolet rays. In order to reduce the risk of such side-effects it is desirable to limit outdoor activities or to shield the entire transdermal preparation, so as to avoid exposure to ultraviolet rays.
In order to help prevent occurrence of photodermatosis, it has been attempted in recent years to develop ketoprofen-containing tape preparations containing ultraviolet absorbers with a high degree of skin migration (see PTL 1), or gel patches provided with supports modified so as to shield ultraviolet rays (see PTL 2). Presumably, by minimizing photodecomposition of ketoprofen and reducing production of ketoprofen decomposition products it is possible to minimize occurrence of side-effects such as photodermatosis.